Apparatus for feeding and compressing gases and liquids

ABSTRACT

A pump having a cylindrical casing and carrying therewithin a tubular, multilayered strip attached along an axial surface line on the inner surface of the casing wherein the circumference of the strip is less than the inner circumference of the casing. Mounted therewithin for rotation and for urging the strip against the inside of the casing is a roller which is driven along a shaft mounted coaxially in the casing.

United States Patent [72] lnventor Otto P. Lutz Bienroder Weg 53, 33Braunschweig, Germany [21] Appl. No. 829,261 [22] Filed June 2, 1969[45] Patented Aug. 3,1971

[54] APPARATUS FOR FEEDING AND COMPRESSING GASES AND LIQUIDS 5 Claims,3Drawing Figs.

[52] U.S.Cl 417/475, 417/476 [51] Int. Cl ..F04b 43/08, F04!) 43/12,F04b 45/06 [50] Field otSeareh 103/148, 149;230/l68; 91/57;4l8/45,156;417/474,476, 477

[56] References Cited UNITED STATES PATENTS 645,132 3/1900 Robinson91/57 1,983,033 12/1934 Hutchison 103/149 2,885,966 5/1959 Ford 103/1492,946,291 7/1960 Roebig 103/149 2,970,748 2/1961 Bendall 230/1683,212,627 10/1965 Beebee 74/232 3,397,739 8/1968 Miller 103/149 FOREIGNPATENTS 179,324 5 1922 Great Britain 103/149 1,191,815 4/1959 France103/149 Primary Examiner-Carlton R. Croyle Assistant Examiner-John J.Vrablik Altorney- Browdy and Neimark ABSTRACT: A pump having acylindrical casing and carrying therewithin a tubular, multilayeredstrip attached along an axial surface line on the inner surface of thecasing wherein the circumference of the strip is less than the innercircumference of the casing. Mounted therewithin for rotation and forurging the strip against the inside of the casing is a roller which isdriven along a shaft mounted coaxially in the casing Patented Aug. 3,1971 Fig-2 Inventor APPARATUS FUR FEEDING AND COMPRESSING GASES ANDLIQUIDS This invention relates to an apparatus for feeding andcompressing gases and liquids. it is an object of the invention toprovide such an apparatus which is of greatest simplicity and low inprice, which further has little volume of construction and works withlow friction when in operation, but which at the same time is capableofbeing run at high speeds.

According to the invention this problem is solved by a cylindricalcasing compromising plane end walls, a tubular, singlelayered ormultilayered strip or tape mounted within said casing and attached alongan axial surface line on the inner surface of the casing, thecircumference of said strip being smaller than the inner circumferenceof the casing, and its width being so dimensioned that its lateral edgesare at a minimum distance from the end walls, a driving shaft mountedcoaxially and rotatably in the end walls, means secured on said drivingshaft and disposed within said strip, which means force the stripagainst the inner wall of the casing substantially linearly, inlet andoutlet openings provided in side-by-side arrangement in the cylindricalcasing, between which openings the said strip is secured to the casing,the outlet opening being provided with a check valve.

The invention and further features thereof are illustrated in theaccompanying drawing and hereinafter described in detail with referenceto the drawing, wherein FIG. 1 is a cross section of the apparatusaccording to the invention;

FIG. 2 is an axial longitudinal section of the apparatus according tothe invention with two working chambers and,

FIG. 3 is a sectional detail taken along the edge of the strip or tapeadjacent the end walls.

As will be seen from H0. 1 the apparatus comprises a casing 1 closed atits ends by plane end walls. A tubular single layered or multilayeredstrip or tape 3 is mounted along an axial surface line on the innersurface of said casing by means of attachment blocks 2. Thecircumference of said strip is smaller than the inner circumference ofthe casing l. A driving shaft 4 is axially rotatably mounted in bearingsprovided in the end walls in said casing 1, the said driving shaft beingdisposed so as to have its driving end extending beyond one of said endwalls to the outside. The width of the strip 3 is so dimensioned that itextends along the length of the casing and butts against the end wallswith a minimum ofclearance so that it may move relatively to the endwalls.

The strip 3 is forced against the inner surface of the casing lsubstantially linearly by means of a cylindrical roller 5, or aplurality of rollers, as indicated at 6 in FIG. 1. The roller isrotatably mounted on an axle 7 which in turn is radially guided on pins8, the latter being firmly connected with the driving shaft 4, forexample, as shown in the drawing by means of bores in the driving shaft.Pressure springs 9 are provided on the pins 8 between the driving shaft4 and the axle 7 by which pressure springs the contact pressure for theroller 5 is produced.

An inlet opening 12 and an outlet opening 13 are provided inside-by-side arrangement in the cylindrical casing l. The said twoopenings are immediately adjacent the axial surface line along which thestrip 3 is secured to the inner surface of the casing. A check valve isarranged in the outlet opening, which valve is under the pressure ofsprings 15.

THe driving shaft 4 and the roller 5 rotate anticlockwise as indicatedin FIG. 1 by the arrow; thereby a suction chamber and a pressure chamber11 are provided. As can readily be seen from the drawing the volume inthe pressure chamber 11 will be decreased as the roller 5 proceeds androtates, and the medium trapped in said chamber will be discharged intothe outlet opening 13. At the same time the suction chamber 10 will beincreased so that fresh medium is sucked in through the inlet opening12. The suction chamber 10 has reached its highest volume if the roller5 has arrived at the surface line of the casing along which the strip issecured. After the roller has passed the opening 12 the volume to be fedis entirely trapped in the pressure chamber 11 and is then dischargedthrough the outlet opening 13.

In the operation described above the strip is merely continuously rolledalong the inner wall of the casing 1 so that the material of said stripwill be worn only moderately. In order to prevent the strip 3 fromkinking where it is attached to the easing the attachment blocks 2 arecurved so as to correspond to the minimum radius of curvature of thestrip 3 occurring in operation.

The strip 3 consists of an elastic metal layer 31, for example of a verythin spring sheet metal, steel or any other metal. SUitably the strip ismade of a plurality of layers, at least one additional layer 32 beingmade of a plastic material having a low frictional index, for example,polytetrafluoroethylene. Preferably, said plastic layer 32 slightlyextends as shown in FIG. 3 beyond the lateral edges of the sheet metaland frictionally engages the end walls 20 of the casing so as to obtaina good sealing effect.

The apparatus above described has the advantage that it is of greatestsimplicity and low in price. Further, the apparatus has a high suctionvolume but little volume of construction. Since the strip substantiallyrolls along there occurs only a minimum friction. As the pressurechamber practically reduces to zero when the roller 5 approaches theoutlet opening 13, and accordingly the clearance volume particularly canbe made zero, high degrees of compression are possible. Finally, theapparatus can be operated at high speeds.

in the embodiment shown in FIG. 2 working chambers are provided whichare separated from each other by a partition wall 16 which has two planesurfaces. A strip of the tape described above, in this case indicated by3a and 3b, is mounted in each chamber. The said strips are securedadjacent their lateral edges by means of small attachment blocks 2a.

One end of the driving shaft 4 is mounted in a bearing bush 17 providedin the end wall 18 while the other end ofsaid driving shaft is rotatablymounted in a bearing bush [9 provided in the end wall 20. As is furthershown in FIG. 2 the two rollers 5a and 5b and their axles 7a and 7b areeach mounted on a pair of pins and 8b which are staggered by Saidrollers 5a and 5b are of a width which is somewhat smaller than thedistance between the attachment blocks 2a so as to allow the rollers topass freely between the attachment blocks. By the inflexibility of thestrip 30 or 3b a linear contact will be achieved in spite of the smallerwidth of said rollers 5a and 5b. By the staggered arrangement of therollers 5a and 5b a more uniform feed and a more uniform charging loadwill be achieved and the driving shaft statically balanced.

The shape of the casing of the single-acting apparatus according to FIG.1 is easily derivable from the shape of the casing shown in HQ. 2. Thecasing which substantially is of cylindrical form may also beconstructed in a different way. FOr example, instead of constructing theend wall 18 integral with the casing said end wall may as well beconstructed so as to be removable as is the end wall 20.

lclaim:

1. An apparatus for feeding and compressing gases and liquids,comprising a cylindrical casing having plane shaft mounted walls, atubular multilayered strip having at least one layer of spring sheetmetal and mounted within said casing along an axial surface line on theinner surface of the casing, means to attach said strip to said casingalong said axial surface line comprising two attachment blocks eachmounted in axial direction adjacent the lateral edges on the innersurface of the strip, the circumference of said strip being smaller thanthe inner circumference of the casing and its width being so dimensionedthat its lateral edges are at a minimum distance from the end walls, adriving shaft mounted coaxially and rotatably in the end walls, andhaving arms extending radially outwardly, means secured on said arms ofsaid driving shaft and disposed within said strip, which means forcesaid strip against the inner wall of the casing substantially linearly,said means comprising a rotatably mounted cylindrical roller buttingagainst the inner surface of said strip, the roller being of a widthwhich is somewhat smaller than the distance between the attachmentblocks, inlet and outlet openings provided in side-by-side arrangementin the cylindrical casing, between which openings the strip is securedto the casing along the surface line thereof, the outlet opening beingprovided with a check valve.

2. An apparatus as claimed in claim 1, characterized in that the stripcomprises at least one layer ofa spring sheet metal and a layer ofplastic material.

3. An apparatus as claimed in claim 2, characterized in that the layerof plastic material slightly extends beyond the lateral edges of thespring sheet metal.

4. An apparatus as claimed in claim 1, characterized in that the rolleris rotatably mounted on an axle which is radially slidably supported inthe arms, resilient means being provided to force the axle away from thedriving shaft.

5. An apparatus as claimed in claim 1, characterized in that at leasttwo working chambers are provided in side-by-side arrangement in acasing, which are separated by a partition wall, each of said chamberscomprising a strip, and the contact means on the driving shaft beingangularly staggered.

1. An apparatus for feeding and compressing gases and liquids,comprising a cylindrical casing having plane shaft mounted walls, atubular multilayered strip having at least one layer of spring sheetmetal and mounted within said casing along an axial surface line on theinner surface of the casing, means to attach said strip to said casingalong said axial surface line comprising two attachment blocks eachmounted in axial direction adjacent the lateral edges on the innersurface of the strip, the circumference of said strip being smaller thanthe inner circumference of the casing and its width being so dimensionedthat its lateral edges are at a minimum distance from the end walls, adriving shaft mounted coaxially and rotatably in the end walls, andhaving arms extending radially outwardly, means secured on said arms ofsaid driving shaft and disposed within said strip, which means forcesaid strip against the inner wall of the casing substantially linearly,said means comprising a rotatably mounted cylindrical roller buttingagainst the inner surface of said strip, the roller being of a widthwhich is somewhat smaller than the distance between the attachmentblocks, inlet and outlet openings provided in side-by-side arrangementin the cylindrical casing, between which openings the strip is securedto the casing along the surface line thereof, the outlet opening beingprovided with a check valve.
 2. An apparatus as claimed in claim 1,characterized in that the strip comprises at least one layer of a springsheet metal and a layer of plastic material.
 3. An apparatus as claimedin claim 2, characterized in that the layer of plastic material slightlyextends beyond the lateral edges of the spring sheet metal.
 4. Anapparatus as claimed in claim 1, characterized in that the roller isrotatably mounted on an axle which is radially slidably supported in thearms, resilient means being provided to force the axle away from thedriving shaft.
 5. An apparatus as claimed in claim 1, characterized inthat at least two working chambers are provided in side-by-sidearrangement in a casing, which are separated by a partition wall, eachof said chambers comprising a strip, and the contact means on thedriving shaft being angularly staggered.